GB759958A - Improvements in or relating to pin-fin assemblies for use in heat exchangers or other light weight wire structures - Google Patents

Abstract

759,958. Making heat-exchangers and structural elements. GIER, J. R. April 30, 1954, No. 12640/54. Class 83 (2). [Also in Group XIII] A method of forming a structural element, in particular a heat exchanger, comprises flattening a wire at intervals along its length to form plain portions 10 alternating with flattened or ligament portions 11, Figs. 1 and 2, and then bending the wire to the sinuous shape shown in Fig. 4 and afterwards subjecting the wire to a further deformation to the shape shown in Fig. 5. The ligament portions 11 are then bonded to heat exchange surfaces, e.g. plates 21, Fig. 7, or tubes, and the portions 10 extend from these surfaces as pin-fins. Adjacent ligament portions 11 may be angularly offset as shown in Fig. 15, so that when the wire is bent a double row of pin-fins is formed (Fig. 16). The wires may be of stainless steel in which case plain steel strips 41, Fig. 11, are resistance welded to the ligaments 11, the strips 41 being afterwards brazed to the heat exchange surfaces. Alternatively (Fig. 12) composite strips of stainless steel 52 and plain steel 53 are welded to the ligaments 11 with the plain steel surfaces 53 outermost, these latter surfaces being afterwards brazed to the heat exchange surfaces 54. The pin-fins may be threaded or grooved (Fig. 21, not shown) and may be of aerofoil crosssection.